A new interactive image analysis procedure for analyzing and comparing slit-lamp camera images of human eye lenses has been developed and implemented on the DCRT Image Processing System. This procedure features television camera image digitization, interest area delineation by means of a flexible oval template, data calibration and standardization, and computation of a variety of statistical measurements for descriptive and comparative purposes. Also, an experiment to analyze the contricution to measurement variance due to photographic procedure, film and film processing, digitization, and analyst judgement factors has been designed.